The following is a conventional method for measuring the potentials inside and outside a cell (hereinafter, cellular potentials) or other cellular electrophysiological phenomena caused by cellular electrophysiological activities.
As a conventional cellular electrophysiological measurement device, it is known to measure cellular potentials by using a substrate having a cell holding means and an electrode provided on the cell holding means. In this cellular electrophysiological measurement device, the cell holding means captures a cell and places the cell in such a manner as to separate the space in the device into two regions. The separated two regions provide a potential difference therebetween, and the potential difference can be measured to determine changes in the cellular potential. One such type of cellular electrophysiological measurement device is disclosed in International Publication No. WO02/055653.
FIG. 19 is a sectional view showing the aforementioned conventional cellular electrophysiological measurement device. Cellular electrophysiological measurement device 130 (hereinafter, device 130) includes well 120 with measuring solution 121A and substrate 123 provided with cell holder 131 (hereinafter, holder 131) for capturing and holding cell 122. Holder 131 is formed of depression 124, opening 125, and through-hole 126 connected to depression 124 through opening 125. Depression 124, opening 125, and through-hole 126 are formed in substrate 123.
The space of device 130 with the aforementioned structured is separated by cell 122 into two regions. One region contains measuring solution 121A provided with reference electrode 127 and the other region contains measuring solution 121B provided with measuring electrode 128. Measuring electrode 128 outputs the potential of measuring solution 121B contained in through-hole 126 through wiring.
When the potentials inside and outside the cell are measured with device 130, cell 122 is sucked by such as a suction pump (unillustrated) from the through-hole 126 side, thereby being tightly held on the opening of depression 124. Then, the electrical signal generated when cell 122 is activated is detected with measuring electrode 128.